If you provide a service I want, sure. I’m more than happy to pay for software and moderately happy to pay for subscriptions, but with it I expect ironclad guarantees about data being local, and absolutely no tracking.
No, because I have a commercially licensed version of Proxie available, which is more flexible since it doesn’t require code modification, and (in my opinion) produces prettier output.
Additionally, there is no incentive to buy httpretty since it is distributed under a permissive license - by using it, I would likely never see an ad (though I would, of course, carefully audit the code before adopting it to ensure it does not do anything underhand).